Improved furnace for finishing sheet-iron



UNiTn STATES \V. DEWEES WOOD, OF MCKEESPORT, PENNSYLVANIA.

iMPROVED FURNACE FOR FINISHING SHEET-IRON.

To all whom it may concern:

Be it known that l, W. Dnwnns WOOD, of of McKeesport, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Furnaces for Finishing' Sheet-Iron; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, in which- Figure lis a longitudinal vertical section of my furnace. Fig. 2 is a transverse vertical section thereof. Fig. 3 is a top view of the perforated tloor of the heating-chamber, the appearance of the roof of the chamber being similar thereto.

In the several figures like letters of reference denote similar parts.

The object of my invention is to overcome a practical difficulty in heatin plates of sheetiron preparatory to the tinishn g rolling with sufficient uniformity.

After the iron has been reduced to sheets of the requisite degree of thinness they are heated in a furnace before being operated upon by the finishing-rolls. Being too thin to be operated upon singly, two or more sheets are placed together in a pack and passed through the rolls, by which means the sheets can be rolled thinner than a single sheet could be if rolled alone. In order to secure uniformity of thickness and smooth nish in the sheets thus rolled in a pack, it is very importa-nt that all parts of each of the sheets should be, as nearly as possible, at the same degree of heat, and as the sheets, being thin, heat very rapidly, and are only left in the furnace for this purpose for two or three minutes, it is essential that the heat should be uniform in all parts of the heating-chamber. rIhis it has been found very diticult to accomplish, as that partof the heating-chamber which is nearest to the re is usually a good deal hott( r than the other end, near to the door at which the sheets are introduced. To remedy this difficulty, I furnish the heating-chamber with a perforated cover and floor, and conduct the heat and tire from the furnace in two streamsone above the cover and the other below the Hoor-and as thc heat and tire have to enter the chamber to reach the escape-flue, they do so through these pcrforations, which gradu- Speciteation forming parl ot' Letters Patent No. @6,@4 E, dated March 14, 1865.

ally increase in diameter as their distance from the tire increases. The sheets of iron to be heated I support on the edge of angular railings raised above the floor, so that theheat may have free access to all parts of the pack of sheets placed in the heating-chamber.

To enable others skilled in the art to construct and use my improved heatingfurnace, I will proceed to describe its construction more minutely.

In the drawings, a. is the fire-chamber of the furnace, constructed in the usual way; b, the grating or fire bed. The furnace is built of brick, those parts which are exposed to the action of the fire being constructed or lined with tire-brick. c is the back wall of the furnace, which has an opening, d, extending transversely across it, about midway between the fire-bed b and the roof e of the furnace, through which opening all the iiame, heated air, and fuliginous matter pass on their way to the tlues ff, situate on each side of the furnace near to the front end, at which the sheets of iron are introduced. The iluesff are made one in each of the side walls,g g, and are arched, so as to meet together in one chimney above the furnace.

The iiame and heated air are not allowed to pass at once into the heat-ing chamber Il., being prevented from doing so by a perpendicular blank wall, 7, which is placed parallel to and at a little distance from the back wall, c, of the fire-chamber. The heating chamber h is formed by the side walls, g g, the blank wall k, the front wall, t, and a floor, m, and cover n. The iioor m of the heating chamber is made of tire-bricks and is raised above the bottom of the furnace, so as to leave a flue, p, under the entire oor m, as shown in Figs. l and 2. The floor is arched, as shown in Fig. 2, the arch springing from the side walls, g g. The cover n is also made of fire-brick, and is arched in the same manner as the floor. It is situate sufficiently below the roof c of the furnace to leave a tine, q, extending over the entire cover not' the heating-chamber. The tluesp and g open at their rear end into the space r between the blank wall 7c and the tire-wall c, so that the flame and heat issuing from the fire-chamber a, through the passage d, enter the space r, where they are parted into two streams,

one passing upward through the ilue q over the cover n, and the other downward through the flue p under the floor m.

As the heated air and flame must enter the heating-chamber h to reach the exit iiucs f j', openingsz' t', 85e., are made in the bricks composing the covering n and door m of the heating-chamber for this purpose. These openf ings M may be circular, as shown in Fig. 3, and are smaller at the rear end ofthe heatingchamber near the rc than at the front end near the doors, gradually increasing in diameter from the rear to the front. The object of this is to equalize as much as possible the amount of flame and heat which enter ythe heating-chamber at all points above and below.

Instead of placing the packs of sheets of iron to be heated on the floor of the furnace, they are supported above the loor on the rails t t, about equidistant between the floor and cover. These rails, of which there are two or more parallel rows, extending from front to rear of the heating-chamber, are made of triangular prisms ot' fire-brick, a cross section of which is shown in Fig. 2. These prisms t t are sustained by pillars, a u, built up from the arched floor fm, and are so placed on them that one of the angles of the triangle forms the top ofthe rail on which the sheets of iron rest, so that only a very small part of the surface of the sheets is in contact with the rails, and almost the entire surface aboveand below is exposed to the direct action of the lire.

The door s opens directly into the heatingchamber, and through it the sheets of iron are inserted and removed. The top of the rails t t is on a level with the bottom of the doorway s.

Having thus described my improved heating-furnace for sheet-iron, what I claim as my invention, and desire to secure by Letters Patent, is-

1. Constructing the heatingchamber with a perforated cover and floor, so arranged.rel atively to the re-chamber and flues as that the fire and heated air shall enter the chamber through these openings in the cover and door at various points above and below tle level of the sheets of iron placed therein, substantially as and for the purposes hereinbefore described.

2. In combination with the perforated floor of the heatingchamber, the rails tt,'raised above the level of the floor, for supporting the sheets g of iron.

In testimony whereof I, the said W. DE- WEES NOOD, have hereunto set my hand.

XV. DEVEES WOOD. 

